Mortality risk for kidney transplant candidates with diabetes: a population cohort study.

AIMS/HYPOTHESIS: It is unclear whether kidney transplant candidates with diabetes have equitable transplantation opportunities or have divergent survival probabilities stratified by kidney replacement therapy. The aim of this study was to investigate these two issues using national transplant registry data in the UK. METHODS: A cohort study was undertaken of prospectively collected registry data of all wait-listed people with kidney failure receiving dialysis in the UK. All people listed for their first kidney-alone transplant between 2000 and 2019 were included. Stratification was done for cause of kidney failure. Primary outcome was all-cause mortality. Time-to-death from listing was analysed using adjusted non-proportional hazard Cox regression models, with transplantation handled as a time-dependent covariate. RESULTS: A total of 47,917 wait-listed people with kidney failure formed the total study cohort, of whom 6594 (13.8%) had diabetes classified as cause of kidney failure. People with kidney failure with diabetes comprised 27.6% of the cohort (n=3681/13,359) that did not proceed to transplantation vs only 8.4% (n=2913/34,558) of the cohort that received a transplant (p<0.001). Kidney transplant candidates with diabetes were more likely to be older, of male sex and of ethnic minority background compared with those without diabetes. In an adjusted analysis, compared with remaining on dialysis, any kidney transplant provided survival benefit for wait-listed kidney transplant candidates regardless of diabetes as cause of kidney failure (RR 0.26 [95% CI 0.25, 0.27], p<0.001). CONCLUSIONS/INTERPRETATION: Kidney transplant candidates with diabetes have a lower chance of transplantation despite better survival after kidney transplantation vs remaining on dialysis. The reasons for this require further investigation to ensure equal transplantation opportunities.

Conservative kidney management and kidney supportive care: core components of integrated care for people with kidney failure.

Integrated kidney care requires synergistic linkage between preventative care for people at risk for chronic kidney disease and health services providing care for people with kidney disease, ensuring holistic and coordinated care as people transition between acute and chronic kidney disease and the 3 modalities of kidney failure management: conservative kidney management, transplantation, and dialysis. People with kidney failure have many supportive care needs throughout their illness, regardless of treatment modality. Kidney supportive care is therefore a vital part of this integrated framework, but is nonexistent, poorly developed, and/or poorly integrated with kidney care in many settings, especially in low- and middle-income countries. To address this, the International Society of Nephrology has (i) coordinated the development of consensus definitions of conservative kidney management and kidney supportive care to promote international understanding and awareness of these active treatments; and (ii) identified key considerations for the development and expansion of conservative kidney management and kidney supportive care programs, especially in low resource settings, where access to kidney replacement therapy is restricted or not available. This article presents the definitions for conservative kidney management and kidney supportive care; describes their core components with some illustrative examples to highlight key points; and describes some of the additional considerations for delivering conservative kidney management and kidney supportive care in low resource settings.

A meta-analysis of randomized controlled clinical trials for implications of acute treatment effects on glomerular filtration rate for long-term kidney protection.

Pharmacologic interventions to slow chronic kidney disease progression, such as ACE-inhibitors, angiotensin receptor blockers, or sodium glucose co-transporter 2 inhibitors, often produce acute treatment effects on glomerular filtration rate (GFR) that differ from their long-term chronic treatment effects. Observational studies assessing the implications of acute effects cannot distinguish acute effects from GFR changes unrelated to the treatment. Here, we performed meta-regression analysis of multiple trials to isolate acute effects to determine their long-term implications. In 64 randomized controlled trials (RCTs), enrolling 154,045 participants, we estimated acute effects as the mean between-group difference in GFR slope from baseline to three months, effects on chronic GFR slope (starting at three months after randomization), and effects on three composite kidney endpoints defined by kidney failure (GFR 15 ml/min/1.73m2 or less, chronic dialysis, or kidney transplantation) or sustained GFR declines of 30%, 40% or 57% decline, respectively. We used Bayesian meta-regression to relate acute effects with treatment effects on chronic slope and the composite kidney endpoints. Overall, acute effects were not associated with treatment effects on chronic slope. Acute effects were associated with the treatment effects on composite kidney outcomes such that larger negative acute effects were associated with lesser beneficial effects on the composite kidney endpoints. Associations were stronger when the kidney composite endpoints were defined by smaller thresholds of GFR decline (30% or 40%). Results were similar in a subgroup of interventions with supposedly hemodynamic effects that acutely reduce GFR. For studies with GFR 60 mL/min/1.73m2 or under, negative acute effects were associated with larger beneficial effects on chronic GFR slope. Thus, our data from a large and diverse set of RCTs suggests that acute effects of interventions may influence the treatment effect on clinical kidney outcomes.

Genome-wide analysis identifies MYH11 compound heterozygous variants leading to visceral myopathy corresponding to late-onset form of megacystis-microcolon-intestinal hypoperistalsis syndrome.

Megacystis-microcolon-hypoperistalsis-syndrome (MMIHS) is a rare and early-onset congenital disease characterized by massive abdominal distension due to a large non-obstructive bladder, a microcolon and decreased or absent intestinal peristalsis. While in most cases inheritance is autosomal dominant and associated with heterozygous variant in ACTG2 gene, an autosomal recessive transmission has also been described including pathogenic bialellic loss-of-function variants in MYH11. We report here a novel family with visceral myopathy related to MYH11 gene, confirmed by whole genome sequencing (WGS). WGS was performed in two siblings with unusual presentation of MMIHS and their two healthy parents. The 38 years-old brother had severe bladder dysfunction and intestinal obstruction, whereas the 30 years-old sister suffered from end-stage kidney disease with neurogenic bladder and recurrent sigmoid volvulus. WGS was completed by retrospective digestive pathological analyses. Compound heterozygous variants of MYH11 gene were identified, associating a deletion of 1.2 Mb encompassing MYH11 inherited from the father and an in-frame variant c.2578_2580del, p.Glu860del inherited from the mother. Pathology analyses of the colon and the rectum revealed structural changes which significance of which is discussed. Cardiac and vascular assessment of the mother was normal. This is the second report of a visceral myopathy corresponding to late-onset form of MMIHS related to compound heterozygosity in MYH11; with complete gene deletion and a hypomorphic allele in trans. The hypomorphic allele harbored by the mother raised the question of the risk of aortic disease in adults. This case shows the interest of WGS in deciphering complex phenotypes, allowing adapted diagnosis and genetic counselling.

Association of Kidney Cysts With Progressive CKD After Radical Nephrectomy.

RATIONALE & OBJECTIVE: Simple kidney cysts, which are common and usually considered of limited clinical relevance, are associated with older age and lower glomerular filtration rate (GFR), but little has been known of their association with progressive chronic kidney disease (CKD). STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: Patients with presurgical computed tomography or magnetic resonance imaging who underwent a radical nephrectomy for a tumor; we reviewed the retained kidney images to characterize parenchymal cysts at least 5mm in diameter according to size and location. EXPOSURE: Parenchymal cysts at least 5mm in diameter in the retained kidney. Cyst characteristics were correlated with microstructural findings on kidney histology. OUTCOME: Progressive CKD defined by dialysis, kidney transplantation, a sustained≥40% decline in eGFR for at least 3 months, or an eGFR<10mL/min/1.73m2 that was at least 5mL/min/1.73m2 below the postnephrectomy baseline for at least 3 months. ANALYTICAL APPROACH: Cox models assessed the risk of progressive CKD. Models adjusted for baseline age, sex, body mass index, hypertension, diabetes, eGFR, proteinuria, and tumor volume. Nonparametric Spearman's correlations were used to examine the association of the number and size of the cysts with clinical characteristics, kidney function, and kidney volumes. RESULTS: There were 1,195 patients with 50 progressive CKD events over a median 4.4 years of follow-up evaluation. On baseline imaging, 38% had at least 1 cyst, 34% had at least 1 cortical cyst, and 8.7% had at least 1 medullary cyst. A higher number of cysts was associated with progressive CKD and was modestly correlated with larger nephrons and more nephrosclerosis on kidney histology. The number of medullary cysts was more strongly associated with progressive CKD than the number of cortical cysts. LIMITATIONS: Patients who undergo a radical nephrectomy may differ from the general population. A radical nephrectomy may accelerate the risk of progressive CKD. Genetic testing was not performed. CONCLUSIONS: Cysts in the kidney, particularly the medulla, should be further examined as a potentially useful imaging biomarker of progressive CKD beyond the current clinical evaluation of kidney function and common CKD risk factors. PLAIN-LANGUAGE SUMMARY: Kidney cysts are common and often are considered of limited clinical relevance despite being associated with lower glomerular filtration rate. We studied a large cohort of patients who had a kidney removed due to a tumor to determine whether cysts in the retained kidney were associated with kidney health in the future. We found that more cysts in the kidney and, in particular, cysts in the deepest tissue of the kidney (the medulla) were associated with progressive kidney disease, including kidney failure where dialysis or a kidney transplantation is needed. Patients with cysts in the kidney medulla may benefit from closer monitoring.

Smoking Timing, Healthy Diet, and Risk of Incident CKD Among Smokers: Findings From UK Biobank.

RATIONALE & OBJECTIVE: Although smoking is a recognized risk factor for chronic kidney disease (CKD), the relationship between the time smoking is initiated after awakening each day and CKD remains largely unstudied. This study examined the association between this timing and the risk of CKD, and the potential interactions of smoking timing with other risk factors for the occurrence of CKD. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: A total of 32,776 participants in the UK Biobank with complete data on the time from waking to the first cigarette and free of prevalent CKD were included. EXPOSURE: Time from waking to the first cigarette. OUTCOME: Incident CKD cases. ANALYTICAL APPROACH: Cox proportional hazards regression was used to investigate the associations between the time smoking is initiated each day and the risk of CKD. The potential interactions of smoking timing with risk factors in relationship to CKD risk were assessed on both multiplicative and additive scales. RESULTS: During a median follow-up period of 12 years, 940 incident CKD cases occurred. Shorter durations of time from waking to the first cigarette were associated with a higher risk of incident CKD (P trend=0.01). Compared with>120 minutes, the adjusted hazard ratio (HR) associated with smoking timing was 1.28 (95% CI, 0.92-1.80) for 61-120 minutes, 1.48 (95% CI, 1.11-1.96) for 30-60 minutes, 1.36 (95% CI, 1.01-1.88) for 5-15 minutes, and 1.70 (95% CI, 1.22-2.37) for<5 minutes, respectively. Furthermore, there was a significant additive interaction and multiplicative interactions between the timing of smoking and a healthy diet score (P for additive interaction=0.01; P for multiplicative interaction = 0.004). LIMITATIONS: Generalizability, possible residual confounding, limiting causal inference. CONCLUSIONS: These findings reveal a significant association between the shorter time from waking to the first cigarette and a higher CKD risk. The magnitude of these associations was greater in the setting of an unhealthy diet. PLAIN-LANGUAGE SUMMARY: This study explored the association of the daily timing of first cigarette smoking and the occurrence of kidney disease. Further, we addressed whether this association was influenced by the quality of the diet. The study found that smoking very soon after waking, especially when combined with a poorer quality diet, was associated with a significantly increased risk of developing chronic kidney disease. This research emphasizes the value of healthier lifestyle choices for kidney health.

Kidney Care in Times of Crises: A Review.

The global burden of kidney disease is increasing, paralleled by a rising number of natural and man-made crises. During these tumultuous times, accessing vital health care resources becomes challenging, posing significant risks to individuals, particularly those with kidney disease. This review delves into the impact of crises on kidney disease, with a particular focus on acute kidney injury (AKI), kidney failure, and kidney transplant. Patients experiencing crush injuries leading to AKI may encounter delayed diagnosis due to the chaotic nature of disasters and limited availability of resources. In chronic crises such as conflicts, patients with kidney failure are particularly affected, and deviations from dialysis standards are unfortunately common, impacting morbidity and mortality rates. Additionally, crises also disrupt access to kidney transplants, potentially compromising transplant outcomes. This review underscores the critical importance of preparedness measures and proactive management for kidney disease in crisis settings. Collaborative efforts among government bodies, rescue teams, health care providers, humanitarian agencies, and nongovernmental organizations are imperative to ensure equitable and reasonable care for kidney disease patients during times of crises, with the aim of saving lives and improving outcomes.

Associations of Urine and Plasma Metabolites With Kidney Failure and Death in a Chronic Kidney Disease Cohort.

RATIONALE & OBJECTIVE: Biomarkers that enable better identification of persons with chronic kidney disease (CKD) who are at higher risk for disease progression and adverse events are needed. This study sought to identify urine and plasma metabolites associated with progression of kidney disease. STUDY DESIGN: Prospective metabolome-wide association study. SETTING & PARTICIPANTS: Persons with CKD enrolled in the GCKD (German CKD) study with metabolite measurements, with external validation within the ARIC (Atherosclerosis Risk in Communities) Study. EXPOSURES: 1,513 urine and 1,416 plasma metabolites (Metabolon Inc) measured at study entry using untargeted mass spectrometry. OUTCOMES: Main end points were kidney failure (KF) and a composite kidney end point (CKE) of KF, estimated glomerular filtration rate<15mL/min/1.73m2, or a 40% decrease in estimated glomerular filtration rate. Death from any cause was a secondary end point. After a median of 6.5 years of follow-up, 500 persons had experienced KF, 1,083 had experienced the CKE, and 680 had died. ANALYTICAL APPROACH: Time-to-event analyses using multivariable proportional hazard regression models in a discovery-replication design with external validation. RESULTS: 5,088 GCKD study participants were included in analyses of urine metabolites, and 5,144 were included in analyses of plasma metabolites. Among 182 unique metabolites, 30 were significantly associated with KF, 49 with the CKE, and 163 with death. The strongest association with KF was observed for plasma hydroxyasparagine (HR, 1.95; 95% CI, 1.68-2.25). An unnamed metabolite measured in plasma and urine was significantly associated with KF, the CKE, and death. External validation of the identified associations of metabolites with KF or the CKE revealed directional consistency for 88% of observed associations. Selected associations of 18 metabolites with study outcomes have not been previously reported. LIMITATIONS: Use of observational data and semiquantitative metabolite measurements at a single time point. CONCLUSIONS: The observed associations between metabolites and KF, the CKE, or death in persons with CKD confirmed previously reported findings and also revealed several associations not previously described. These findings warrant confirmatory research in other study cohorts. PLAIN-LANGUAGE SUMMARY: Incomplete understanding of the variability of chronic kidney disease (CKD) progression motivated the search for new biomarkers that would help identify people at increased risk. We explored metabolites in plasma and urine for their association with unfavorable kidney outcomes or death in persons with CKD. Metabolomic analyses revealed 182 metabolites significantly associated with CKD progression or death. Many of these associations confirmed previously reported findings or were validated by analysis in an external study population. Our comprehensive screen of the metabolome serves as a valuable foundation for future investigations into biomarkers associated with CKD progression.

Sex and the Relationship Between Cardiometabolic Risk Factors and Estimated GFR Decline: A Population-Based Cohort Study.

RATIONALE & OBJECTIVE: Females have a higher prevalence of chronic kidney disease (CKD) than males, but are less likely to be treated with kidney replacement therapy (KRT). We studied the interaction between sex and the association of cardiometabolic risk factors for the decline in kidney function over time. STUDY DESIGN: A population-based cohort study. SETTING & PARTICIPANTS: 1,127,731 adults living in Wales, UK, within the Secure Anonymised Information Linkage Databank. EXPOSURES: Sex and risk factors including age, estimated glomerular filtration rate (eGFR), cardiometabolic conditions, smoking, and socioeconomic deprivation. These risk factors were defined using primary care records. OUTCOMES: The yearly declines in eGFR and the risk of incident kidney failure defined as long-term KRT and/or sustained eGFR<15mL/min/1.73m2. ANALYTICAL APPROACH: Linear mixed effects models and Cox proportional hazards analysis. RESULTS: The average decline in eGFR age ≤73 was equal in males and females. After age 73, eGFR decline was faster in males than females, particularly for males with heart failure (males -1.22 mL/min/1.73m2 per year: 95% confidence interval (CI) -1.25 to -1.20 versus females -0.87mL/min/1.73m2: CI -0.89 to -0.85) and current smokers (males -1.58 mL/min/1.73m2 per year: CI -1.60 to -1.55 versus females -1.27 mL/min/1.73m2: CI -1.29 to -1.25). Socioeconomic deprivation was one of the most impactful risk factors on eGFR decline among females age >73, whereas cardiometabolic risk factors were more important among males. Older females at baseline were less likely to develop incident kidney failure than older males (p-value for age<0.001). LIMITATIONS: Study of people who were almost exclusively White and who had blood laboratory test data. Reliance on creatinine-based eGFR. Albuminuria and body mass index data were incomplete. CONCLUSIONS: eGFR decline was faster in males than in females especially in the setting of heart failure and smoking. Socioeconomic deprivation was an important risk factor associated with eGFR decline, particularly for females. While further work is required to explore less well-recognised risk factors these findings may inform clinical management strategies of CKD overall and within sex-specific groups.

Vitamin D Metabolites Before and After Kidney Transplantation in Patients Who Are Anephric.

RATIONALE & OBJECTIVE: Kidneys are vital for vitamin D metabolism, and disruptions in both production and catabolism occur in chronic kidney disease. Although vitamin D activation occurs in numerous tissues, the kidneys are the most relevant source of circulating active vitamin D. This study investigates extrarenal vitamin D activation and the impact of kidney transplantation on vitamin D metabolism in patients who are anephric. STUDY DESIGN: Case series. SETTING & PARTICIPANTS: Adult patients with previous bilateral nephrectomy (anephric) not receiving active vitamin D therapy evaluated at the time of (N=38) and 1 year after (n=25) kidney transplantation. ANALYTICAL APPROACH: Chromatography with tandem mass spectrometry was used to measure vitamin D metabolites. Activity of CYP24A1 [24,25(OH)2D/25(OH)D] and CYP27B1 [1α,25(OH)2D/25(OH)D] is expressed as metabolic ratios. Differences between time points were evaluated by paired t-test or Wilcoxon matched-pairs signed-rank test. RESULTS: At time of transplantation, 1α,25(OH)2D was detectable in all patients (4-36pg/mL). There was a linear relationship between 25(OH)D and 1α,25(OH)2D levels (r=0.58, P<0.001), with 25(OH)D explaining 34% of the variation in 1α,25(OH)2D levels. There were no associations between 1α,25(OH)2D and biointact parathyroid hormone (PTH) or fibroblast growth factor 23 (FGF-23). One year after transplantation, 1α,25(OH)2D levels recovered (+205%), and CYP27B1 activity increased (+352%). Measures of vitamin D catabolism, 24,25(OH)2D and CYP24A1 activity increased 3- to 5-fold. Also, at 12 months after transplantation, 1α,25(OH)2D was positively correlated with PTH (ρ=0.603, P=0.04) but not with levels of 25(OH)D or FGF-23. LIMITATIONS: Retrospective, observational study design with a small cohort size. CONCLUSIONS: Low-normal levels of 1α,25(OH)2D was demonstrated in anephric patients, indicating production outside the kidneys. This extrarenal CYP27B1 activity may be more substrate driven than hormonally regulated. Kidney transplantation seems to restore kidney CYP27B1 and CYP24A1 activity, as evaluated by vitamin D metabolic ratios, resulting in both increased vitamin D production and catabolism. These findings may have implications for vitamin D supplementation strategies in the setting of kidney failure and transplantation. PLAIN-LANGUAGE SUMMARY: Vitamin D activation occurs in multiple tissues, but the kidneys are considered the only relevant source of circulating levels. This study investigates vitamin D activation outside the kidneys by measuring vitamin D metabolites in 38 patients without kidneys. Active vitamin D was detectable in all patients, indicating production outside of the kidneys. There was a strong relationship between active and precursor vitamin D levels, but no association with mineral metabolism hormones, indicating that vitamin D production was more substrate dependent than hormonally regulated. One year after kidney transplantation, active vitamin D levels increased 2-fold and breakdown products increased 3-fold, indicating that production and degradation of the hormone recovers after kidney transplantation. These findings are relevant for future research into vitamin D supplementation in kidney failure.

The prevalence of HIV resistance mutations and their influence on the shedding of HIV-1 into peritoneal dialysis effluent.

HIV drug resistance mutations (HIVDRMs) are important determinants of therapeutic effects and outcomes even in end-stage kidney failure (ESKF) people living with HIV (PLWHIV). This study evaluated the prevalence of HIVDRMs and their effect on the shedding of HIV-1 into peritoneal dialysis (PD) effluents. This cross-sectional study of PLWHIV and having ESKF and managed with antiretroviral therapy (ART) and PD, collected enrolled patients' demographic information, clinical and laboratory data, and sequenced HIV-1 RNA in unsuppressed plasma and PD effluent samples. HIV viral load and HIVDRMs were determined using qualitative polymerase chain reaction (qPCR) and Stanford University HIVDRM Database, respectively. There were 60 participants recruited with a median age of 43.0 (interquartile range [IQR], 38.0-47) years and were predominantly on abacavir (88.3%), lamivudine (98.3%), and efavirenz (70%) for a median duration of 8 (IQR, 5-11) years. Among participants with detectable HIV-1 in PD effluents, the prevalence of HIVDRMs was 62.5% (5/8) compared to 7.7% (4/52) among those with undetectable HIV-1 (p = 0.001) with non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance mutations predominating. On Spearman's correlation analysis, high plasma HIV levels (ρ = 0.649, p < 0.001), T-cell CD4 count (ρ = -0370, p < 0.004), serum creatinine (ρ = -0.396, p < 0.002), and white blood cell count (ρ = -0.294, p < 0.023) levels were significant factors correlated with the detection of HIV-1 in PD effluents. Moreover, HIVDRMs presence (ρ = 0.504, p < 0.001) particularly NNRTI resistance (ρ = 0.504, p < 0.001) were also significantly correlated with detection of HIV-1 in PD effluents. The presence of HIVDRMs, high plasma HIV viral load, and T-cell CD4 count were correlated with HIV-1 shedding into PD effluents.

Evaluation of a proteomic signature coupled with the kidney failure risk equation in predicting end stage kidney disease in a chronic kidney disease cohort.

BACKGROUND: The early identification of patients at high-risk for end-stage renal disease (ESRD) is essential for providing optimal care and implementing targeted prevention strategies. While the Kidney Failure Risk Equation (KFRE) offers a more accurate prediction of ESRD risk compared to static eGFR-based thresholds, it does not provide insights into the patient-specific biological mechanisms that drive ESRD. This study focused on evaluating the effectiveness of KFRE in a UK-based advanced chronic kidney disease (CKD) cohort and investigating whether the integration of a proteomic signature could enhance 5-year ESRD prediction. METHODS: Using the Salford Kidney Study biobank, a UK-based prospective cohort of over 3000 non-dialysis CKD patients, 433 patients met our inclusion criteria: a minimum of four eGFR measurements over a two-year period and a linear eGFR trajectory. Plasma samples were obtained and analysed for novel proteomic signals using SWATH-Mass-Spectrometry. The 4-variable UK-calibrated KFRE was calculated for each patient based on their baseline clinical characteristics. Boruta machine learning algorithm was used for the selection of proteins most contributing to differentiation between patient groups. Logistic regression was employed for estimation of ESRD prediction by (1) proteomic features; (2) KFRE; and (3) proteomic features alongside KFRE. RESULTS: SWATH maps with 943 quantified proteins were generated and investigated in tandem with available clinical data to identify potential progression biomarkers. We identified a set of proteins (SPTA1, MYL6 and C6) that, when used alongside the 4-variable UK-KFRE, improved the prediction of 5-year risk of ESRD (AUC = 0.75 vs AUC = 0.70). Functional enrichment analysis revealed Rho GTPases and regulation of the actin cytoskeleton pathways to be statistically significant, inferring their role in kidney function and the pathogenesis of renal disease. CONCLUSIONS: Proteins SPTA1, MYL6 and C6, when used alongside the 4-variable UK-KFRE achieve an improved performance when predicting a 5-year risk of ESRD. Specific pathways implicated in the pathogenesis of podocyte dysfunction were also identified, which could serve as potential therapeutic targets. The findings of our study carry implications for comprehending the involvement of the Rho family GTPases in the pathophysiology of kidney disease, advancing our understanding of the proteomic factors influencing susceptibility to renal damage.

Coronary Artery Disease in Patients Undergoing Hemodialysis: A Problem that Sounds the Alarm.

Chronic kidney disease (CKD) is affecting more and more individuals over time. The importance of the increased prevalence is enhanced by the close association with the increased risk of poor individual outcomes such as death, fatal and non-fatal cardiovascular (CV) events and progression to end stage kidney disease (ESKD). ESKD requires replacement treatment such as hemodialysis (HD), a particular and complex context that unfortunately has been rarely considered in observational studies in the last few decades. The current perspective of HD as a bridge to kidney transplant requires greater attention from observational and experimental research both in the prevention and treatment of CV events in ESKD patients. We present a narrative review by performing a literature review to extrapolate the most significant articles exploring the CV risk, in particular coronary artery disease (CAD), in ESKD and evaluating possible innovative diagnostic and therapeutic tools in these patients. The risk of CAD increases linearly when the estimated glomerular filtration rate (eGFR) declines and reached the most significant level in ESKD patients. Several diagnostic techniques have been evaluated to predict CAD in ESKD such as laboratory tests (Troponin-T, N-terminal pro b-type natriuretic peptide, alkaline phosphatase), echocardiography and imaging techniques for vascular calcifications evaluation. Similarly, treatment is based on lifestyle changes, medical therapy and invasive techniques such as coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). Unfortunately in the literature there are no clear indications of the usefulness and validity of biomarkers and possible treatments in ESKD patients. Considering the ESKD weight in terms of prevalence and costs it is necessary to implement clinical research in order to develop prognostic reliable biomarkers for CV and CAD risk prediction, in patients with ESKD. It should be highlighted that HD is a peculiar setting that offers the opportunity to implement research and facilitates patient monitoring by favoring the design of clinical trials.

Dihydropyridine Calcium Channel Blockers and Kidney Outcomes.

BACKGROUND: Early trials of dihydropyridine calcium channel blockers (DCCBs) suggest a detrimental effect on intraglomerular pressure and an association with albuminuria. OBJECTIVE: We sought to evaluate the associations of DCCB initiation with albuminuria and kidney failure with replacement therapy (KFRT) and to determine whether renin-angiotensin system (RAS) blockade modified these associations. DESIGN: We conducted a target trial emulation study using a new user, active comparator design and electronic health record data from Geisinger Health. PARTICIPANTS: We included patients without severe albuminuria or KFRT who were initiated on a DCCB or thiazide (active comparator) between January 1, 2004, and December 31, 2019. MAIN MEASURES: Using inverse probability of treatment weighting, we performed doubly robust Cox proportional hazards regression to estimate the association of DCCB initiation with incident severe albuminuria (urine albumin to creatinine ratio > 300 mg/g) and KFRT, overall and stratified by RAS blocker use. KEY RESULTS: There were 11,747 and 26,758 eligible patients initiating a DCCB and thiazide, respectively, with a weighted baseline mean age of 60 years, systolic blood pressure of 143 mm Hg, and eGFR of 86 mL/min/1.73 m2, and with a mean follow-up of 8 years. Compared with thiazides, DCCBs were significantly associated with the development of severe albuminuria (hazard ratio [HR], 1.29; 95% confidence interval [CI], 1.16-1.43), with attenuation of risk in the presence of RAS blockade (P for interaction < 0.001). The risk of KFRT was increased among patients without RAS blockade (HR, 1.66; 95% CI, 1.19-2.31), but not with RAS blockade (P for interaction = 0.005). CONCLUSIONS: DCCBs were associated with increased risk of albuminuria and, in the absence of RAS blockade, KFRT. These findings suggest coupling DCCB therapy with RAS blockade may mitigate adverse kidney outcomes.

Left atrial appendage occlusion in patients suffering from advanced chronic kidney disease (stage 4 and 5). Long-term follow-up.

INTRODUCTION AND OBJECTIVES: Advanced chronic kidney disease (A-CKD) combined with atrial fibrillation increases the risk of both thrombogenic and bleeding events. Left atrial appendage occlusion (LAAO) may be an alternative to oral anticoagulation to prevent thromboembolic events. We aimed to evaluate the outcomes of LAAO in patients with A-CKD. METHODS: Comparison at long-term follow-up of patients diagnosed with and without A-CKD (eGFR<30 mL/min/1.73 m2 ) who underwent LAAO between 2009 and May 2022. RESULTS: Five hundred seventy-three patients were included. Eighty-one (14%) were diagnosed with A-CKD. There were no differences in sex, age, and cardiovascular risk factors, except for diabetes which was more frequent in patients with A-CKD. The control group had higher rates of stroke, both ischemic and hemorrhagic. There were no differences in the CHA2 DS2 -VASc score, although A-CKD patients had a higher bleeding risk according to the HASBLED scale. Global procedural success was 99.1%. At follow-up, there were no differences in stroke rate: at 1-year (HR: 1.22, IC-95%: 0.14-10.42, p = 0.861); at 5-years (HR: 0.60, IC-95%: 0.08-4.58, p = 0.594). Although bleeding events were higher in the A-CKD group, no differences were found in major bleeding (defined BARC ≥ 3) at 1-year (HR: 1.34, IC-95%: 0.63-2.88, p = 0.464) or at 5-years follow-up (HR: 1.30, IC-95%: 0.69-2.48, p = 0.434). Mortality rate at 5 years was higher in the A-CKD patients (HR: 1.84, IC-95%: 1.18-2.87, p = 0.012). CONCLUSIONS: LAAO is an effective and safe treatment in A-CKD patients to prevent ischemic events and bleeding. This strategy could be an alternative to oral anticoagulation in this high-risk group of patients.

Relative survival in patients with cancer and kidney failure.

BACKGROUND AND HYPOTHESIS: The population with kidney failure is at increased risk of cancer and associated mortality. Relative survival can provide insight into the excess mortality, directly or indirectly, attributed to cancer in the population with kidney failure. METHODS: We estimated relative survival for people all ages receiving dialysis (n = 4089) and kidney transplant recipients (n = 3253) with de novo cancer, and for the general population with cancer in Australia and New Zealand (n = 3 043 166) over the years 1980-2019. The entire general population was the reference group for background mortality, adjusted for sex, age, calendar year and country. We used Poisson regression to quantify excess mortality ratios. RESULTS: Five-year relative survival for all-site cancer was markedly lower than the general population for people receiving dialysis (0.25, 95%CI:0.23-0.26) and kidney transplant recipients (0.55, 95%CI:0.53-0.57). In dialysis, excess mortality was more than double (2.16, 95%CI:2.08-2.25) that of the general population with cancer and for kidney transplant recipients 1.34 higher (95%CI:1.27-2.41). There was no difference in excess mortality from lung cancer between people with kidney failure and the general population with cancer. Comparatively, there was a significant survival deficit for people with kidney failure, compared to the general population with cancer, for melanoma, breast cancer and prostate cancers. CONCLUSION: Decreased cancer survival in kidney failure may reflect differences in multi-morbidity burden, reduced access to treatment, or greater harm from or reduced efficacy of treatments. Our findings support research aimed at investigating these hypotheses.

Population-wide eGFR percentiles in younger adults and clinical outcomes.

BACKGROUND AND HYPOTHESIS: Identifying meaningful estimated glomerular filtration rate (eGFR) reductions in younger adults (<65 years) could guide prevention efforts. To aid in interpretation and identification of young adults at risk, we examined the association of population-level eGFR percentiles relative to the median by age and clinical outcomes. METHODS: We conducted a retrospective cohort study of 8.7 million adults from Ontario, Canada from age 18 to 65 from 2008 to 2021 with an eGFR measure (both single outpatient value and repeat measures). We calculated median eGFR values by age and examined the association of reduced eGFR percentiles (≤10th, 5th, 2.5th and 1st) with outcomes using time to event models. Outcomes were a composite of all-cause mortality, major adverse cardiac outcomes (MACE) with/without heart failure (MACE+) and kidney failure as well as each component individually. RESULTS: From age 18 to 65, the median eGFR declined with age (range 128 to 90) and across percentiles [eGFR ranges 102 to 68 for ≤10th, 96 to 63 for ≤5th, 90 to 58 for ≤2.5th and 83 to 54 for 1st]. The adjusted rate for any adverse outcome was elevated at ≤ 10th percentile (HR 1.14 95%CI 1.10-1.18) and was consistent for all-cause mortality, MACE, MACE+ and predominant for kidney failure (HR 5.57 95%CI 3.79-8.19) compared to the median eGFR for age. Young adults with an eGFR in the lower percentiles were less likely to be referred to a specialist, have a repeat eGFR or albumin to creatinine ratio measure. CONCLUSIONS: eGFR values at the 10th percentile or lower based on a population-level distribution are associated with adverse clinical outcomes and in younger adults (18 to 39) this corresponds to a higher level of eGFR that may be underrecognized. Application of population-based eGFR percentiles may aid interpretation and improve identification of younger adults at risk.

Prescribing patterns and medications costs in patients on maintenance hemodialysis and peritoneal dialysis.

BACKGROUND AND HYPOTHESIS: Polypharmacy is a significant clinical issue for patients on dialysis but has been incompletely studied. We investigated the prevalence and costs of polypharmacy in a population-based cohort of participants treated with hemodialysis (HD) or peritoneal dialysis (PD). METHODS: We studied adults aged ≥ 20 years in Alberta, Canada receiving maintenance HD or PD as of March 31, 2019. We characterized participants as users of 0-29 drug categories of interest and those aged ≥ 65 as users/non-users of potentially inappropriate medications (PIM). We calculated the number of drug categories, daily pill burden, total annual cost, and annual cost per participant, and compared this to an age- and sex-matched cohort from the general Alberta population. RESULTS: Among 2 248 participants (mean age 63 years; 39% female) on HD (n = 1 781) or PD (n = 467), the median number of prescribed drug categories was 6 [interquartile range (IQR) 4, 8]; median daily pill burden was 8.0 (IQR 4.6, 12.6) pills/day, with 5% prescribed ≥ 21.7 pills/day, and 16.5% prescribed ≥ 15 pills/day. Twelve % were prescribed at least one drug that is contraindicated in kidney failure. The median annual per participant cost was ${\$}$3,831, totaling approximately ${\$}$11.6 million annually for all participants. When restricting to the 1 063 participants aged ≥ 65, the median number of PIM categories was 2 (IQR 1, 2), with a median PIM pill burden of 1.2 pills/day (IQR 0.5, 2.4). Compared to PD participants, HD participants had similar daily pill burden, higher use of PIM, and higher annual per participant cost. Pill burden and associated costs for participants on dialysis were more than 3-fold and 10-fold higher, respectively, compared to the matched participants from the general population. CONCLUSION: Participants on dialysis have markedly higher use of prescription medications and associated costs than the general population. Effective methods to de-prescribe in the dialysis population are needed.

Treatment strategies of the thromboembolic risk in kidney failure patients with atrial fibrillation.

The incidence and prevalence of atrial fibrillation (AF) in patients affected by kidney failure, i.e. glomerular filtration rate <15 ml/min/1.73 m2, is high and probably underestimated. Numerous uncertainties remain regarding how to prevent thromboembolic events in this population because both cardiology and nephrology guidelines do not provide clear recommendations. The efficacy and safety of oral anticoagulant therapy (OAC) in preventing thromboembolism in patients with kidney failure and AF has not been demonstrated for either vitamin K antagonists (VKAs) or direct anticoagulants (DOACs). Moreover, it remains unclear which is more effective and safer, because estimated creatinine clearance <25-30 ml/min was an exclusion criterion in the randomized controlled trials (RCTs). Three RCTs comparing DOACs and VKAs in kidney failure failed to reach the primary endpoint, as they were underpowered. The left atrial appendage is the main source of thromboembolism in the presence of AF. Left atrial appendage closure (LAAC) has recently been proposed as an alternative to OAC. RCTs comparing the efficacy and safety of LAAC versus OAC in kidney failure were terminated prematurely due to recruitment failure. A recent prospective study showed a reduction in thromboembolic events in haemodialysis patients with AF and undergoing LAAC compared with patients taking or not taking OAC. We review current treatment standards and discuss recent developments in managing the thromboembolic risk in kidney failure patients with AF. The importance of shared decision-making with the multidisciplinary team and the patient to consider individual risks and benefits of each treatment option is underlined.

A Comparison of Sodium-Glucose Co-Transporter 2 Inhibitor Kidney Outcome Trial Participants with a Real-World Chronic Kidney Disease Primary Care Population.

BACKGROUND/HYPOTHESIS: Observational studies suggest sodium-glucose co-transporter-2 (SGLT2) inhibitor kidney outcome trials are not representative of the broader population of people with chronic kidney disease (CKD). However, there are limited data on the generalisability to those without co-existing type 2 diabetes (T2D), and the representativeness of the EMPA-KIDNEY trial has not been adequately explored. We hypothesised that SGLT2 inhibitor kidney outcome trials are more representative of people with co-existing T2D than those without, and that EMPA-KIDNEY is more representative than previous trials. METHODS: A cross-sectional analysis of adults with CKD in English primary care was conducted using the Oxford-Royal College of General Practitioners Clinical Information Digital Hub. The proportions that met the eligibility criteria of SGLT2 inhibitor kidney outcome trials were determined, and their characteristics described. Logistic regression analyses were performed to identify factors associated with trial eligibility. RESULTS: Of 6,670,829 adults, 516,491 (7.7%) with CKD were identified. In the real-world CKD population, 0.9%, 2.2%, and 8.0% met the CREDENCE, DAPA-CKD, and EMPA-KIDNEY eligibility criteria, respectively. All trials were more representative of people with co-existing T2D than those without T2D. Trial participants were 9-14 years younger than the real-world CKD population, and had more advanced CKD, including higher levels of albuminuria. A higher proportion of the CREDENCE (100%), DAPA-CKD (67.6%) and EMPA-KIDNEY (44.5%) trial participants had T2D compared to the real-world CKD population (32.8%). Renin-angiotensin system inhibitors were prescribed in almost all trial participants, compared to less than half of the real-world CKD population. Females were under-represented and less likely to be eligible for the trials. CONCLUSION: SGLT2 inhibitor kidney outcome trials represent a sub-group of people with CKD at high risk of adverse kidney events. Out study highlights the importance of complementing trials with real-world studies, exploring the effectiveness of SGLT2 inhibitors in the broader population of people with CKD.